This invention relates to a method and apparatus for separating drilling mud and waste materials into a concentrated solid phase that can be readily disposed of and a pure water phase.
It is well known that in the drilling of oil and gas wells, large quantities of water are used in the makeup of drilling mud. It is also well known that during the course of drilling operations, the drilling mud becomes contaminated with various materials and that both during the course of drilling and at the completion of drilling operations, the drilling mud must be disposed of. It is further well known that in drilling operations, various waste streams are produced from spillage, wash water that is used to wash down drilling rig equipment, galley waste and from rain water runoff and the like.
Heretofore, little attention has been paid to methods or equipment for disposing of drilling mud and waste materials. In most prior art land drilling operations, drilling mud and waste materials have been merely dumped into pits that are abandoned following the drilling operations. Unfortunately, in many drilling operations that are carried out on offshore rigs and along inland waterways, liquid waste streams from drilling operations have been merely discharged into the sea or into inland waterways. Recently, however, emphasis has been shifting toward ecologically safe disposal of drilling mud and waste materials. Now, severe limitations are placed on various drilling operations whereby drilling mud and waste materials can no longer be discharged into the environment or merely abandoned in open pits or other waste dumps at the end of drilling operations.
Several methods have been suggested for disposing of drilling mud and waste materials. Probably the most common method now employed in "safe" disposal of drilling mud and waste materials is to collect the drilling mud and waste materials into barges, trucks and the like and transport them to some location where the drilling mud and waste materials can be disposed of. Such a collection and transport pose several problems. The first problem is in the sheer volume of materials that must be collected, stored and transported to some treatment site. Secondly, handling of drilling mud and waste materials is difficult and very costly. Finally, such known methods as centrifuge separations, screening and the like still produce relatively viscous mud-like streams that are difficult to dispose of.
It is therefore an object of this invention to provide an improved method and apparatus for separating drilling mud and waste materials into a concentrated solid phase that can be easily disposed of and relatively pure water.
It is another object of this invention to provide an improved method and apparatus that can be used at or near a drilling site separate drilling mud and waste materials into a concentrated solid waste phase that be readily disposed of and relatively pure water.
It is yet another object of this invention to provide a method and apparatus for separating drilling mud and waste materials to provide relatively pure water that can be reused in the drilling operations or safely discharged into the environment.